jdk/src/share/classes/java/lang/invoke/MethodHandleStatics.java
author jrose
Wed, 18 Jan 2012 17:34:30 -0800
changeset 11535 c248aa7dfe5d
parent 10419 12c063b39232
child 13423 17843fff200d
permissions -rw-r--r--
7077803: java.lang.InternalError in java.lang.invoke.MethodHandleNatives.init Summary: Use correct access token for unreflecting MHs where setAccessible(true) Reviewed-by: never, twisti

/*
 * Copyright (c) 2011, Oracle and/or its affiliates. All rights reserved.
 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
 *
 * This code is free software; you can redistribute it and/or modify it
 * under the terms of the GNU General Public License version 2 only, as
 * published by the Free Software Foundation.  Oracle designates this
 * particular file as subject to the "Classpath" exception as provided
 * by Oracle in the LICENSE file that accompanied this code.
 *
 * This code is distributed in the hope that it will be useful, but WITHOUT
 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
 * version 2 for more details (a copy is included in the LICENSE file that
 * accompanied this code).
 *
 * You should have received a copy of the GNU General Public License version
 * 2 along with this work; if not, write to the Free Software Foundation,
 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
 *
 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
 * or visit www.oracle.com if you need additional information or have any
 * questions.
 */

package java.lang.invoke;

import java.security.AccessController;
import java.security.PrivilegedAction;

/**
 * This class consists exclusively of static names internal to the
 * method handle implementation.
 * Usage:  {@code import static java.lang.invoke.MethodHandleStatics.*}
 * @author John Rose, JSR 292 EG
 */
/*non-public*/ class MethodHandleStatics {

    private MethodHandleStatics() { }  // do not instantiate

    static final boolean DEBUG_METHOD_HANDLE_NAMES;
    static {
        final Object[] values = { false };
        AccessController.doPrivileged(new PrivilegedAction<Void>() {
                public Void run() {
                    values[0] = Boolean.getBoolean("java.lang.invoke.MethodHandle.DEBUG_NAMES");
                    return null;
                }
            });
        DEBUG_METHOD_HANDLE_NAMES = (Boolean) values[0];
    }

    /*non-public*/ static String getNameString(MethodHandle target, MethodType type) {
        if (type == null)
            type = target.type();
        MemberName name = null;
        if (target != null)
            name = MethodHandleNatives.getMethodName(target);
        if (name == null)
            return "invoke" + type;
        return name.getName() + type;
    }

    /*non-public*/ static String getNameString(MethodHandle target, MethodHandle typeHolder) {
        return getNameString(target, typeHolder == null ? (MethodType) null : typeHolder.type());
    }

    /*non-public*/ static String getNameString(MethodHandle target) {
        return getNameString(target, (MethodType) null);
    }

    /*non-public*/ static String addTypeString(Object obj, MethodHandle target) {
        String str = String.valueOf(obj);
        if (target == null)  return str;
        int paren = str.indexOf('(');
        if (paren >= 0) str = str.substring(0, paren);
        return str + target.type();
    }

    static void checkSpreadArgument(Object av, int n) {
        if (av == null) {
            if (n == 0)  return;
        } else if (av instanceof Object[]) {
            int len = ((Object[])av).length;
            if (len == n)  return;
        } else {
            int len = java.lang.reflect.Array.getLength(av);
            if (len == n)  return;
        }
        // fall through to error:
        throw newIllegalArgumentException("Array is not of length "+n);
    }

    // handy shared exception makers (they simplify the common case code)
    /*non-public*/ static RuntimeException newIllegalStateException(String message) {
        return new IllegalStateException(message);
    }
    /*non-public*/ static RuntimeException newIllegalStateException(String message, Object obj) {
        return new IllegalStateException(message(message, obj));
    }
    /*non-public*/ static RuntimeException newIllegalArgumentException(String message) {
        return new IllegalArgumentException(message);
    }
    /*non-public*/ static RuntimeException newIllegalArgumentException(String message, Object obj) {
        return new IllegalArgumentException(message(message, obj));
    }
    /*non-public*/ static RuntimeException newIllegalArgumentException(String message, Object obj, Object obj2) {
        return new IllegalArgumentException(message(message, obj, obj2));
    }
    /*non-public*/ static Error uncaughtException(Exception ex) {
        throw new InternalError("uncaught exception", ex);
    }
    private static String message(String message, Object obj) {
        if (obj != null)  message = message + ": " + obj;
        return message;
    }
    private static String message(String message, Object obj, Object obj2) {
        if (obj != null || obj2 != null)  message = message + ": " + obj + ", " + obj2;
        return message;
    }
}